MC33912_10 Datasheet, PDF (34/94 Pages) Freescale Semiconductor, Inc – LIN System Basis Chip with DC Motor Pre-driver and Current Sense

FUNCTIONAL DEVICE OPERATIONS
OPERATIONAL MODES
MC33912G5AC / MC34912G5AC
HVSE
MOD1:2
HSx
HSxOP
HSxCL
Interrupt
Control
Module
VDD
PWMHSx
Control
on/off
Status
High Side Driver
charge pump
open load detection
current limitation
over-temperture shutdown (interrupt maskable)
high voltage shutdown (maskable)
VDD
VS2
PWMIN
HSx
Wakeup
Module
Figure 17. High Side Drivers HS1 and HS2
Open Load Detection
Each high side driver signals an open load condition if the
current through the high side is below the open load current
threshold.
The open load condition is indicated with the bits HS1OP
and HS2OP in the High Side Status Register (HSSR).
Current Limitation
Each high side driver has an output current limitation. In
combination with the over-temperature shutdown the high-
side drivers are protected against over-current and short-
circuit failures.
When the driver operates in the current limitation area, it is
indicated with the bits HS1CL and HS2CL in the HSSR.
Note: If the driver is operating in current limitation mode,
excessive power might be dissipated.
Over-temperature Protection (HS Interrupt)
Both high side drivers are protected against over-
temperature. In case of an over-temperature condition both
high side drivers are shut down and the event is latched in the
Interrupt Control Module. The shutdown is indicated as HS
Interrupt in the Interrupt Source Register (ISR).
A thermal shutdown of the high side drivers is indicated by
setting all HSxOP and HSxCL bits simultaneously.
If the bit HSM is set in the Interrupt Mask Register (IMR),
then an interrupt (IRQ) is generated.
A write to the High Side Control Register (HSCR), when
the over-temperature condition is gone, will re-enable the
high side drivers.
High-voltage Shutdown
In case of a high voltage condition and if the high voltage
shutdown is enabled (bit HVSE in the Mode Control Register
(MCR) is set both high side drivers are shut down.
A write to the High Side Control Register (HSCR), when
the high voltage condition is gone, will re-enable the high side
drivers.
Sleep And Stop Mode
The high side drivers can be enabled to operate in Sleep
and Stop mode for cyclic sensing. Also see Table 6,
Operating Modes Overview.
LOW SIDE OUTPUT PINS LS1 AND LS2
These outputs are two low side drivers intended to drive
relays incorporating the following features:
• PWM capability (software maskable)
• Open load detection
• Current limitation
• Over-temperature shutdown (with maskable interrupt)
• Active clamp (for driving relays)
• High-voltage shutdown (software maskable)
The low side switches are controlled by the bit LS1:2 in the
Low Side Control Register (LSCR).
33912
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Analog Integrated Circuit Device Data
Freescale Semiconductor